From the Dallas Mavericks’ perspective, Monta Ellis was better than advertised. In the Mavs’ 118-109 season-opening win over the Atlanta Hawks on Wednesday night before a sellout crowd of 19,834 at American Airlines Center, Ellis proved he was well worth the three-year, $25 million free-agent contract he signed with the Mavs over the off-season. The feisty shooting guard poured in 32 points on 11-of-17 shooting and also added eight assists for good measure as he made himself right at home in his new surroundings. It was the most points ever by a player in his first game with the Mavs. “Right now I’m in a good rhythm, my teammates did a good job finding me and setting screens,’’ Ellis said. “The main thing I had to do was just be aggressive, attack the basket and make the right plays. “I think we put a great group of guys together, we came out and played Mavs basketball. We played together, we made some mistakes, but we stuck with it.’’ It was a gritty game by both teams, as Ellis teamed with Dirk Nowitzki to help close the door on the Mavs’ 34th season opener. On his way to 24 points and five assists, Nowitzki drilled back-to-back 3-pointers — off passes from Ellis — to stake the Mavs to a 115-102 lead. Ellis then hammered in the final nail with his own 3-pointer. “He just shot the ball so well tonight, and so that was helping his drives out,’’ Nowitzki said of Ellis. “He’s so quick off the bounce and he’s so quick with the ball, and that’s a huge strength.’’ In their first game since revamping the roster with nine new players after missing the playoffs last season, the Mavs led 33-28 after the first period behind 11 points from Ellis and nine from Nowitzki. But Paul Millsap tossed in 10 of his 20 points in the second period as the Hawks took a 55-53 lead at the half. However, Shawn Marion tallied 10 of his 12 points in the third period — Ellis also notched 10 third-quarter points — as the momentum swung back in the Mavs’ favor. The intense game was “exactly what we expected, and it was a very good win for us,’’ coach Rick Carlisle said. “Tough games like this bring the group together.’’ Besides Ellis, Nowitzki and Marion, Vince Carter came off the bench to supply 21 points on 9-of-16 shooting. Carlisle also was impressed with the play of Jose Calderon (11 assists), DeJuan Blair (nine points, five boards), Wayne Ellington (six points, three rebounds), rookie Gal Mekel (nine minutes, three assists).